RELATIONSHIP OF TRIGLYCERIDE ACCUMULATION TO INSULIN-CLEARANCE AND HORMONAL RESPONSIVENESS IN BOVINE HEPATOCYTES

The accumulation of triglycerides in the liver has been associated wit h reduced hepatic function; however, direct evidence that fat accumula tion causes decreased liver function is lacking. Hepatocyte monolayers isolated from ruminating calves with an initial low triglyceride conc entration were either loaded or not loaded with triglycerides by incub ation with 1.5 or 0 mM exogenous nonesterified fatty acids from 12 to 48 h after plating. Basal rates of synthesis of albumin and protein we re not affected by triglycerides in the cell. Inclusion of insulin and glucagon from 12 to 72 h after plating increased rates of albumin and protein synthesis. Hepatocytes loaded with triglycerides were less se nsitive to the hormonal stimulation of albumin and protein synthesis t han were normal hepatocytes. Insulin clearance rates were also lower i n hepatocytes loaded with triglycerides than in normal hepatocytes. De creased insulin clearance and hormonal control of protein synthesis co uld contribute to the etiology of metabolic disorders that are associa ted with periparturient fatty Liver in daily cows.